A Regional Resource for computer-aided Intermediate Voltage Transmission Electron Microscopy (300-400 KV, IVEM) and 3-dimensional (3-D) image analysis will be established & serve the Southwest region of the country. These facilities would be made available immediately to investigators using established techniques and working on biological problems that could clearly benefit from the use of thicker specimens and 3-D imaging. We have directed our plan for core technological research toward the development of technologies that will contribute to research in structural neurobiology as well as cell biology and molecular biology. Our goals for collaboration, service, training and dissemination are all related to expanding the use ot these technologies so that they can become as valuable as possible for the biomedical community We efmphasize the use of computer aided methods for enhancement of image contrast, extraction of accurate 3-dimentional information from within single thick specimens and reconstruction of larger structural complexes with serial thich section analysis. We are planning to use a variety of contrast enhancing methods on model system/biological problems that will clearly benefit from the unique capabilities of a computer-coupled IVEM. These include core technological research activities to: provide new IVEM compatible macromolecular probes; improve penetration of probes into frozen sections; enhance selective staining of subcellular structure; and define the 3-D distributions of and relationships between submicron cell processes in nervous systems with quantitative accuracy. The capabilities to be developed and research accomplishments anticipated in all of the core project areas involving methods of specimen preparation will be augmented by features of the imaging system to be developed. These will include: user interactive modification of operating conditions of the IVEM in order to alter image contrast; microscope-coupled image processing and analysis; and semi-automated 3-D image acquisition and reconstruction facilities. Training of users in the application of the technology will occur at the Resource. In addition, yearly workshops and various other forms of scientific communication will be used to disseminate the to-be- developed Resource technologies.